1. Technical Field
The present invention relates generally to High-Bandwidth Digital Content Protection. More particularly, the invention relates a method, apparatus, and system for enabling and/or disabling Display Data Channel (DDC) access to enable and/or disable High-Bandwidth Digital Content Protection.
2. Background Art
As the digital distribution of television, movies, and music expands, content providers are growing increasingly concerned about the simplicity with which content pirates can copy and share copy protected material. Various digital rights management (DRM) schemes have been developed to ensure that television shows, movies, and music can only be viewed by authorized parties (i.e., paying consumers). The Content Scrambling System (CSS) used to encrypt DVDs and Apple's Fairplay technology are two widely-known examples of DRM schemes. One DRM scheme to protect digital content as it is transmitted over cables between devices is known as High-Bandwidth Digital Content Protection (HDCP). HDCP is a specified method developed by Digital Content Protection, L.L.C., for protecting copyrighted digital content as it travels across connection interfaces and protocols such as DisplayPort (DP), Digital Video Interface (DVI), High-Definition Multimedia Interface (HDMI), Giga-bit Video Interface (GVIF), Digital Light Interface (DLI), Unified Display Interface (UDI), Internet Protocol (IP), Wireless Home Digital Interface (WHDI), Transmission Control Protocol/Internet Protocol (TCP/IP), and Universal Serial Bus (USB). The HDMI specification defines an interface for carrying digital audiovisual content from a source such as a DVD player, to a sink or display device such as a television (TV). As designed by the Digital Content Protection, L.L.C., when the source and sink/display are HDCP compliant, HDCP protected content is displayed but the HDCP protected content cannot be copied and shared. When the source is HDCP compliant and the sink/display is not HDCP compliant, the copy protected material cannot be displayed, copied and/or shared. When the source is HDCP compliant and the sink/display is not HDCP compliant, a non-copy protected material can be displayed, copied and/or shared.
HDCP is designed to prevent copying and sharing of copy protected material. There are issues with interoperability when the material itself is non-copy protected. For example, when an HDCP compliant source such as a laptop is connected to an HDCP compliant sink/display device, non-HDCP protected content cannot, for example, be copied, shared, and replayed at a later time even though the non-HDCP protected content can be displayed on the sink/display device. Many HDCP compliant sources, such as laptops, choose to enable/disable content encryption based on the downstream display's HDCP capabilities. These devices do not “care” if the real-time video content is actually copy protected or non-copy protected and will leave content encryption enabled as soon as the device sees an HDCP compliant sink/display. In the academic field, for example, a university instructor may want students to copy and share content material that is not copy protected (e.g., the professor's PowerPoint presentation). Even though the content is non-copy protected, the students will not be able to copy, replay or share the content because the source and sink/display devices are HDCP compliant.
Accordingly, it is the object of the present invention to correct interoperability issues related to HDCP. The present invention provides a system, apparatus, and method for enabling/disabling Display Data Channel access to enable/disable HDCP.